Vibrio vulnificus is a gram-negative bacterium that is increasingly threatening beachgoers in coastal regions worldwide. Infections can lead to inflammation, sepsis, and in rare cases, death. Researchers have now deciphered the pathogenicity factors of these vibrions.
Until the 1980s there were hardly any infections with Vibrio vulnificus bacteria in the Baltic Sea. For the last two decades, however, the number of Vibrio vulnificus infections in the region has been steadily increasing. The countries bordering the Baltic Sea are reporting up to 30 cases per year with a human mortality rate of about 17%.
On 15 August 2019, the European Center for Disease Control (ECDC) reported a medium risk of infection for V. vulnificus in the Baltic Sea region. The main problem behind the further spread of the vibrios is the gradual increase in sea temperatures. With a water temperature from 13°C onwards, the bacteria find good growth conditions and starting from 20°C, conditions are optimal for their development.
In the mouse model, researchers investigated how vibrions can trigger infections in the water. They found four essential factors that favored a Vibrio infection:
These four pathogenicity factors, which control the growth and also the spread of the vibrions, offer researchers new approaches for future antibiotic therapy. As the infection is often very fulminant, early antibiotic therapy is indicated. At present, combinations of tetracycline and a third-generation cephalosporin are primarily available for adult patients. Alternatively, fluoroquinolones can also be used.
Original work:
Yamazaki K et al., Identification of in vivo Essential Genes of Vibrio vulnificus for Establishment of Wound Infection by Signature-Tagged Mutagenesis. Front Microbiol 2019; doi:10.3389/fmicb.2019.00123